Modelling large-scale predator control measures: Cape-to-City project

New Zealand has an excellent record of conserving its native flora and fauna through pest control measures, especially in large uninhabited areas. Meanwhile large tracts of land owned by private individuals remain relatively unprotected. When it comes to land management decisions such as pest control actions, careful negotiations are required with a wide range of stakeholders with differing views – from cat-loves to rabbit-haters – so that agreements can be reached. The aim of this research project led by Audrey Lustig, Mike Plank and Alex James is to develop a planning tool for predicting the abundance and the likely persistence of New Zealand top mammalian predators in the light of potential changes in management effort across human-dominated landscape. We use the Cape-to-City (C2C) footprint covering 26,000 ha of agricultural land in Hawke’s Ba as a case study. Such modeling can help inform managers on the likelihood of success of a specific pest control action (assuming every landholder participates in the control action). It also allows exploration of some of the mechanisms by which mammal populations might recover after control operations.

The spread model is still being developed to provide more functionality for managers. In particular, we are investigating the ways in which landholders influence one another, how agencies influence landholders, and the presence of key influential landholders who might help catalyze actions are the current focus of research. The work builds on a pre-existing knowledge base and data acquired by the Hawke’s Bay Regional Council, Department of Conservation, Manaaki Whenua and the Biological Heritage Challenge. Such inter-organisational joint effort is common in New Zealand, but to us, what was critical was to bring a more practical insight into our research. Ultimately, the aim of the model is to improve strategic planning for mammal control at regional scales. Also, this model serves as a template for future dynamic maps of other mammal species.